A rapid influenza diagnostic test based on detection of viral neuraminidase activity.

Current methods used for diagnosis of acute infection of pathogens rely on detection of nucleic acids, antigens, or certain classes of antibodies such as IgM. Here we report a virus enzyme assay as an alternative to these methods for detection of acute viral infection. In this method, we used a luciferin derivative as the substrate for detection of the enzyme activity of influenza viral neuraminidase as a means for diagnosis of influenza.

ELMO1 and Dock180, a bipartite Rac1 guanine nucleotide exchange factor, promote human glioma cell invasion.

A distinct feature of malignant gliomas is the intrinsic ability of single tumor cells to disperse throughout the brain, contributing to the failure of existing therapies to alter the progression and recurrence of these deadly brain tumors. Regrettably, the mechanisms underlying the inherent invasiveness of glioma cells are poorly understood. Here, we report for the first time that engulfment and cell motility 1 (ELMO1) and dedicator of cytokinesis 1 (Dock180), a bipartite Rac1 guanine nucleotide exchange factor (GEF), are evidently linked to the invasive phenotype of glioma cells.

Alkylene tether-length dependent gamma-aminobutyric acid type A receptor competitive antagonism by tacrine dimers.

Bis(7)-tacrine was previously demonstrated as an antagonist of gamma-aminobutyric acid type A (GABA(A)) receptors. In this study, the effects of a series of alkylene-linked tacrine dimers on GABA(A) receptors were examined. In radioligand binding assay, the analogues differed in binding affinity for GABA(A) receptors, and potency monotonically increased as the tether was shortened from nine to two methylenes.

CRIT peptide interacts with factor B and interferes with alternative pathway activation.

Complement C2 receptor inhibitor trispanning (CRIT) inhibits the classical pathway (CP) C3 convertase formation by competing with C4b for the binding of C2. The C-terminal 11-amino-acid of the first CRIT-extracellular domain (CRIT-H17) has a strong homology with a sequence in the C4beta chain, which is responsible for the binding of C2. Since the CP and alternative pathway (AP) C3 convertases have many functional and structural similarities, we further investigated the effects of CRIT-H17 on the AP.

Expression of functional recombinant von Willebrand factor-A domain from human complement C2: a potential binding site for C4 and CRIT.

CRIT (complement C2 receptor inhibitor trispanning) is a newly described transmembrane molecule that is capable of binding C2 via its first extracellular domain (ed1). CRIT competes with C4b for the binding of C2. Previous experiments have suggested that a major binding site for C2 is located on short, almost identical peptide sequences of CRIT-ed1 and the beta-chain of C4.

Complement C2 receptor inhibitor trispanning: a novel human complement inhibitory receptor.

The complement system presents a powerful defense against infection and is tightly regulated to prevent damage to self by functionally equivalent soluble and membrane regulators. We describe complement C2 receptor inhibitor trispanning (CRIT), a novel human complement regulatory receptor, expressed on hemopoietic cells and a wide range of tissues throughout the body. CRIT is present in human parasites through horizontal transmission.

Naturally occurring 2'-hydroxyl-substituted flavonoids as high-affinity benzodiazepine site ligands.

Screening of traditional medicines has proven invaluable to drug development and discovery. Utilizing activity-guided purification, we previously reported the isolation of a list of flavonoids from the medicinal herb Scutellaria baicalensis Georgi, one of which manifested an affinity for the benzodiazepine receptor (BDZR) comparable to that of the synthetic anxiolytic diazepam (K(i)=6.4 nM).

Two flavones from Scutellaria baicalensis Georgi and their binding affinities to the benzodiazepine site of the GABAA receptor complex.

A new flavone 6,2'-dihydroxy-5,7,8,6'-tetramethoxyflavone (1) together with one known flavone 5,7,2'-trihydroxy-6,8-dimethoxyflavone (2) were isolated from the roots of Scutellaria baicalensis Georgi. Their structures were elucidated on the basis of spectral evidence and their affinities for the benzodiazepine (BDZ) site of the GABAA receptor complex were evaluated with a radioligand receptor binding assay.

Structure-activity relationships of flavonoids, isolated from Scutellaria baicalensis, binding to benzodiazepine site of GABA(A) receptor complex.

Twenty-six flavonoids were isolated from Scutellaria baicalensis. Their affinities for the benzodiazepine (BDZ) binding site of GABA A receptor have been studied using [ 3H]flunitrazepam binding to rat cortical membranes in vitro. The structure-activity relationships suggested that 2'-OH flavones exhibited the most potent binding affinity, which could lead to the design and discovery of new BDZ receptor ligands.